Altitudinal dispersal process drives community assembly of montane small mammals

Montane small mammals are subjected to strong forces of dispersal limitation and habitat filtering that mainly operate on their community structures along the altitudinal direction. However, so far little is known about the relative contributions of dispersal and niche processes to their community assembly. By applying the newly-proposed PER-SIMPER/DNCI (dispersal–niche continuum index) framework to small mammal occurrence data collected from 21 extensive altitudinal gradients, we quantitatively assess the relative importance of dispersal and niche processes on mammalian community assembly in a large mountainous region of southwest China. We compared the pairwise DNCI values among assemblages from low, middle, and high altitudinal zones and overall DNCI values between glires and insectivores that differ in dispersal abilities to test three explicit (altitudinal connectivity, environmental difference, and dispersal ability) hypotheses. The overall DNCI values for all small mammal species...